According to Eq.(REF ) the order parameter amplitude \(\Delta _0\)  is slightly dependent on the scattering rate.
So, we see that in superconductor with finite value of the order parameter at any point on the Fermi surface
the low temperature thermal conductivity at resonant scattering on defects is weakly dependent from defects concentration. The similar universality is known
for the low temperature thermal conductivity in the superconductors with zeros of the order parameter when the thermal flow is parallel to the plane where the order parameter is equal to zero or parallel to direction on the points of zeros of the second order [1]}, [2]}, [3]}.
